Magnetic structure for reed relays



July 28, 1964 B. D. BIANCO ETAL MAGNETIC STRUCTURE FOR REED RELAYS FiledAug. 31. 1962 Hunter 8. DAL B/ANCO By M. SCATA.

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United States Patent MAGNETIC STRUCTURE FOR REED RELAYS Bruno DalBianco, Milan, and Mario Scata, Monza,

Milan, Italy, assignors to International Standard Electric Corporation,New York, N.Y., a corporation of Delaware Filed Aug. 31, 1962, Ser. No.220,749 Claims priority, application Italy Sept. 5, 1961 2 Claims. (Cl.200-87) This invention relates in general to glass-sealed reedtyperelays and in particular to the magnetic structure for supporting suchrelays in operative relationship with the associated energizing winding.Its principal object is to provide a magnetic structure for a relay ofthe above character which has a small magnetic reluctance, is compact insize and performs a mechanical supporting function.

In prior-art magnetic structures for glass-sealed reed relays, the twosalient poles of such structures were welded to the ends of the reedrelay contact extensions or the poles were in the form of clips whichclamped the noted contact extensions. The operations required forwelding the two contact extensions involved the use of special holdingdevices for supporting the relay while being welded and thus increasedmanufacturing costs. The clip type supporting arrangement is notcompletely satisfactory since the magnetic-contacting area between thecontact extensions and the magnetic poles were necessarily large andsince these connections were both electrical magnetic, poor electricalcontact often resulted.

According to the present invention, the foregoing dis advantages areovercome by providing a magnetic structure which mechanically supportsthe relay during the noted contact welding and which reduces the numberof welding operations per relay. It is thus another object of theinvention to provide a magnetic structure for glass-sealed reed-typerelays in which one pole is provided for mechanically supporting thereed relay and another pole is provided for supporting one contactextension of the relay in abutting relationship with the lastsaid poleto enhance welding operations.

A feature related to the above object resides in the arrangement whereinthe support pole of the magnetic structure is arranged in the form of aring which encircles the outside periphery of the relay.

Other objects and features of the invention will become apparent and theinvention will be best understood when the specification is read inconjunction with the accompanying drawings comprising FIGS. 1 to 3 inwhich:

FIG. 1 shows a perspective view of the magnetic structure of theinvention without any relay being associated therewith;

FIG. 2 shows a side view of the magnetic structure of FIG. 1 togetherwith a relay mounted in position and an energizing coil surrounding themagnetic structure; and

FIG. 3 shows a magnetic structure having two insulated portions formingthe pole pieces of the magnetic core.

Referring now to FIG. 1 of the drawings, the magnetic structurecomprises a core formed from two L-shaped elements 1 and 3 of magneticmaterial of high permeability arranged side by side and a cylindricalring 2 of high permeable material secured to the longer legs of theelements 1 and 3. Elements 1 and 3 may be secured together as bywelding, and ring 2 may likewise be secured to elements 1 and 3 in asimilar fashion. The inside dimension of the ring 2 corresponds to theoutside dimension of the relay envelope to insure a snug fit.

The shorter legs of the L-shaped elements 1 and 3 may be of the samelength or one may be shorter than the other to define a shoulder againstwhich the contact extension of the relay will rest. Such a shoulder isshown in FIG. 1.

The elements 1 and 3 contain apertures indicated by X which provide adefining slot for holding the usual coil insulating washer in properposition.

Referring now to FIG. 2 of the drawings, the magnetic structure is shownwith coil 6 encircling the core portion of elements 1 and 3 and with areed relay 4 supported within ring 2. The shoulder end of the magneticstructure supports one of the contact extensions of the relay 4. Asnoted, the contact extension of the relay may be fixedly secured to themagnetic structure shoulder as by welding.

As a result of this arrangement, the length of the magnetic circuit isshort and the magnetic flux escaping, for instance, from the top end 7of the energizing coil 6 is received on ring 2 which becomes one of thepolar pieces of the magnetic core. The magnetic flux will pass throughthe glass of relay to the movable magnetic contact member and throughthe contact gap thereof to the stationary magnetic member 5. Member 5,through clip 3 has assumed an opposite sign it being magneticallyconnected to the bottom end of the energizing coil 6.

The operating sensitivity of the relay is thus efiiciently increased andthe sealed contact devices can be easily replaced in case of failureWithout impairing the magnetic circuit.

It is obvious that slight modifications of the shape of said magneticcore will permit the use of other relays different from the illustratedtype.

FIG. 3 illustrates the magnetic circuit of FIG. 1 modified for use withcontact devices enclosed in sealed vessels of types other than thoseillustrated in FIG. 2. In this case, the magnetic core comprises twoL-shaped pieces in which the two horizontal opposite and overlappedportions and the arms 8 and 9 are insulated therebetween along thehorizontal portions carrying the energizing coil 6. ,The insulation canbe easily obtained by interposing an insulating material strip 10between said magnetic horizontal overlapped portions 11 and 12,tightening and locking the whole by a tape, which insulates said corefrom the coil. The core end, which was shaped in FIGS. 1 and 2 as atubular ring will be now formed with a second clip clamping the othermagnetic terminal of the relay.

While the principles of the invention have been described above inconnection with specific apparatus and applications, it is to beunderstood that this description is made only by way of example and notas a limitation on the scope of the invention.

What is claimed is:

1. An external magnetic circuit for relays having electrical contacts ofmagnetic material sealed in protective envelopes with a portion of eachcontact extending out of the same end of said envelope, said circuitcomprising a U-shaped structure of high permeable magnetic materialdefining a magnetic core section having first and second salient polepieces, a flux generating winding mounted on said core section forgenerating a magnetic fiux to operate said contacts in response tomagnetic attraction therebetween, one of said pole pieces comprising asupport portion for one end of said envelope independently of any saidcontact extension and the other of said pole pieces comprising a supportportion for the other end of said envelope, the last-said portionelectrically and magnetically contacting one only of said relay contactextensions.

2. An external magnetic circuit for relays having electrical contacts ofmagnetic material sealed in protective envelopes and having a portion ofeach contact extending out of the same end of said envelope, saidcircuit comprising a' U-shaped structure of high permeable magnetic3,142,734 5 4 material defining a magnetic core section having first andReferences Cited in the file of this patent second salient pole pieces,a flux generating winding mounted on said core section 'for generating amagnetic UNITED STATES PATENTS flux to operate said contacts in responseto magnetic at- 1,967,943 Hedill J ly 1934 traction therebetween, one ofsaid pole pieces compris- 5 2,317,695 Pollard Apr. 27, 1943 ing acylindrical ring for encircling the said envelope at 2,963,545 PurzyckiDec. 6, 1960 one end independently of any contact extension and the3,005,072 Brown Oct. 17, 1961 other of said pole pieces comprising ashoulder portion 3,008,019 Scheidig N v, 7 19 1 for supporting the otherend of said envelope, the said 3 04 370 Ad et 1 1 24 19 2 shoulderportion electrically and magnetically contacting 10 one only of saidrelay contact extensions.

1. AN EXTERNAL MAGNETIC CIRCUIT FOR RELAYS HAVING ELECTRICAL CONTACTS OFMAGNETIC MATERIAL SEALED IN PROTECTIVE ENVELOPES WITH A PORTION OF EACHCONTACT EXTENDING OUT OF THE SAME END OF SAID ENVELOPE, SAID CIRCUITCOMPRISING A U-SHAPED STRUCTURE OF HIGH PERMEABLE MAGNETIC MATERIALDEFINING A MAGNETIC CORE SECTION HAVING FIRST AND SECOND SALIENT POLEPIECES, A FLUX GENERATING WINDING MOUNTED ON SAID CORE SECTION FORGENERATING A MAGNETIC FLUX TO OPERATE SAID CONTACTS IN RESPONSE TOMAGNETIC ATTRACTION THEREBETWEEN, ONE OF SAID POLE PIECES COMPRISING ASUPPORT PORTION FOR ONE END OF SAID ENVELOPE INDEPENDENTLY OF ANY SAIDCONTACT EXTENSION AND THE OTHER OF SAID POLE PIECES COMPRISING A SUPPORTPORTION FOR THE OTHER END OF SAID ENVELOPE, THE LAST-SAID PORTIONELECTRICALLY AND MAGNETICALLY CONTACTING ONE ONLY OF SAID RELAY CONTACTEXTENSIONS.